<?php
// +----------------------------------------------------------------------
// | ThinkPHP [ WE CAN DO IT JUST THINK IT ]
// +----------------------------------------------------------------------
// | Copyright (c) 2006-2012 http://thinkphp.cn All rights reserved.
// +----------------------------------------------------------------------
// | Licensed ( http://www.apache.org/licenses/LICENSE-2.0 )
// +----------------------------------------------------------------------
// | Author: liu21st <liu21st@gmail.com>
// +----------------------------------------------------------------------
// $Id: DbPdo.class.php 2729 2012-02-12 04:13:34Z liu21st $


/**
 +-----------------------------
 * PDO数据库驱动类
 +-----------------------------
 */
class DbPdo extends Db {
	
	protected $PDOStatement = null;
	private $table = '';
	
	/**
     +----------------------------------------------------------
	 * 架构函数 读取数据库配置信息
     +----------------------------------------------------------
	 * @access public
     +----------------------------------------------------------
	 * @param array $config 数据库配置数组
     +----------------------------------------------------------
	 */
	public function __construct($config = '') {
		if (! class_exists ( 'PDO' )) {
			throw_exception ( L ( '_NOT_SUPPERT_' ) . ':PDO' );
		}
		if (! empty ( $config )) {
			$this->config = $config;
			if (empty ( $this->config ['params'] )) {
				$this->config ['params'] = array ();
			}
		}
	
	}
	
	/**
     +----------------------------------------------------------
	 * 连接数据库方法
     +----------------------------------------------------------
	 * @access public
     +----------------------------------------------------------
	 * @throws ThinkExecption
     +----------------------------------------------------------
	 */
	public function connect($config = '', $linkNum = 0) {
		if (! isset ( $this->linkID [$linkNum] )) {
			if (empty ( $config ))
				$config = $this->config;
			if ($this->pconnect) {
				$config ['params'] [PDO::ATTR_PERSISTENT] = true;
			}
			//$config['params'][PDO::ATTR_CASE] = C("DB_CASE_LOWER")?PDO::CASE_LOWER:PDO::CASE_UPPER;
			try {
				$this->linkID [$linkNum] = new PDO ( $config ['dsn'], $config ['username'], $config ['password'], $config ['params'] );
			} catch ( PDOException $e ) {
				throw_exception ( $e->getMessage () );
			}
			// 因为PDO的连接切换可能导致数据库类型不同，因此重新获取下当前的数据库类型
			$this->dbType = $this->_getDsnType ( $config ['dsn'] );
			if (in_array ( $this->dbType, array ('MSSQL', 'ORACLE', 'IBASE', 'OCI' ) )) {
				// 由于PDO对于以上的数据库支持不够完美，所以屏蔽了 如果仍然希望使用PDO 可以注释下面一行代码
				throw_exception ( '由于目前PDO暂时不能完美支持' . $this->dbType . ' 请使用官方的' . $this->dbType . '驱动' );
			}
			$this->linkID [$linkNum]->exec ( 'SET NAMES ' . C ( 'DB_CHARSET' ) );
			// 标记连接成功
			$this->connected = true;
			// 注销数据库连接配置信息
			if (1 != C ( 'DB_DEPLOY_TYPE' ))
				unset ( $this->config );
		}
		return $this->linkID [$linkNum];
	}
	
	/**
     +----------------------------------------------------------
	 * 释放查询结果
     +----------------------------------------------------------
	 * @access public
     +----------------------------------------------------------
	 */
	public function free() {
		$this->PDOStatement = null;
	}
	
	/**
     +----------------------------------------------------------
	 * 执行查询 返回数据集
     +----------------------------------------------------------
	 * @access public
     +----------------------------------------------------------
	 * @param string $str  sql指令
     +----------------------------------------------------------
	 * @return mixed
     +----------------------------------------------------------
	 * @throws ThinkExecption
     +----------------------------------------------------------
	 */
	public function query($str) {
		$this->initConnect ( false );
		if (! $this->_linkID)
			return false;
		$this->queryStr = $str;
		//释放前次的查询结果
		if (! empty ( $this->PDOStatement ))
			$this->free ();
		N ( 'db_query', 1 );
		// 记录开始执行时间
		G ( 'queryStartTime' );
		$this->PDOStatement = $this->_linkID->prepare ( $str );
		if (false === $this->PDOStatement)
			throw_exception ( $this->error () );
		$result = $this->PDOStatement->execute ();
		$this->debug ();
		if (false === $result) {
			$this->error ();
			return false;
		} else {
			return $this->getAll ();
		}
	}
	
	/**
     +----------------------------------------------------------
	 * 执行语句
     +----------------------------------------------------------
	 * @access public
     +----------------------------------------------------------
	 * @param string $str  sql指令
     +----------------------------------------------------------
	 * @return integer
     +----------------------------------------------------------
	 * @throws ThinkExecption
     +----------------------------------------------------------
	 */
	public function execute($str) {
		$this->initConnect ( true );
		if (! $this->_linkID)
			return false;
		$this->queryStr = $str;
		$flag = false;
		if ($this->dbType == 'OCI') {
			if (preg_match ( "/^\s*(INSERT\s+INTO)\s+(\w+)\s+/i", $this->queryStr, $match )) {
				$this->table = C ( "DB_SEQUENCE_PREFIX" ) . str_ireplace ( C ( "DB_PREFIX" ), "", $match [2] );
				$flag = ( boolean ) $this->query ( "SELECT * FROM user_sequences WHERE sequence_name='" . strtoupper ( $this->table ) . "'" );
			}
		} //modify by wyfeng at 2009.08.28
		//释放前次的查询结果
		if (! empty ( $this->PDOStatement ))
			$this->free ();
		N ( 'db_write', 1 );
		// 记录开始执行时间
		G ( 'queryStartTime' );
		$this->PDOStatement = $this->_linkID->prepare ( $str );
		if (false === $this->PDOStatement) {
			throw_exception ( $this->error () );
		}
		$result = $this->PDOStatement->execute ();
		$this->debug ();
		if (false === $result) {
			$this->error ();
			return false;
		} else {
			$this->numRows = $result;
			if ($flag || preg_match ( "/^\s*(INSERT\s+INTO|REPLACE\s+INTO)\s+/i", $str )) {
				$this->lastInsID = $this->getLastInsertId ();
			}
			return $this->numRows;
		}
	}
	
	/**
     +----------------------------------------------------------
	 * 启动事务
     +----------------------------------------------------------
	 * @access public
     +----------------------------------------------------------
	 * @return void
     +----------------------------------------------------------
	 */
	public function startTrans() {
		$this->initConnect ( true );
		if (! $this->_linkID)
			return false;
		
		//数据rollback 支持
		if ($this->transTimes == 0) {
			$this->_linkID->beginTransaction ();
		}
		$this->transTimes ++;
		return;
	}
	
	/**
     +----------------------------------------------------------
	 * 用于非自动提交状态下面的查询提交
     +----------------------------------------------------------
	 * @access public
     +----------------------------------------------------------
	 * @return boolen
     +----------------------------------------------------------
	 */
	public function commit() {
		if ($this->transTimes > 0) {
			$result = $this->_linkID->commit ();
			$this->transTimes = 0;
			if (! $result) {
				throw_exception ( $this->error () );
			}
		}
		return true;
	}
	
	/**
     +----------------------------------------------------------
	 * 事务回滚
     +----------------------------------------------------------
	 * @access public
     +----------------------------------------------------------
	 * @return boolen
     +----------------------------------------------------------
	 * @throws ThinkExecption
     +----------------------------------------------------------
	 */
	public function rollback() {
		if ($this->transTimes > 0) {
			$result = $this->_linkID->rollback ();
			$this->transTimes = 0;
			if (! $result) {
				throw_exception ( $this->error () );
			}
		}
		return true;
	}
	
	/**
     +----------------------------------------------------------
	 * 获得所有的查询数据
     +----------------------------------------------------------
	 * @access private
     +----------------------------------------------------------
	 * @return array
     +----------------------------------------------------------
	 * @throws ThinkExecption
     +----------------------------------------------------------
	 */
	private function getAll() {
		//返回数据集
		$result = $this->PDOStatement->fetchAll ( constant ( 'PDO::FETCH_ASSOC' ) );
		$this->numRows = count ( $result );
		return $result;
	}
	
	/**
     +----------------------------------------------------------
	 * 取得数据表的字段信息
     +----------------------------------------------------------
	 * @access public
     +----------------------------------------------------------
	 * @throws ThinkExecption
     +----------------------------------------------------------
	 */
	public function getFields($tableName) {
		$this->initConnect ( true );
		if (C ( 'DB_DESCRIBE_TABLE_SQL' )) {
			// 定义特殊的字段查询SQL
			$sql = str_replace ( '%table%', $tableName, C ( 'DB_DESCRIBE_TABLE_SQL' ) );
		} else {
			switch ($this->dbType) {
				case 'MSSQL' :
				case 'SQLSRV' :
					$sql = "SELECT   column_name as 'Name',   data_type as 'Type',   column_default as 'Default',   is_nullable as 'Null'
        FROM    information_schema.tables AS t
        JOIN    information_schema.columns AS c
        ON  t.table_catalog = c.table_catalog
        AND t.table_schema  = c.table_schema
        AND t.table_name    = c.table_name
        WHERE   t.table_name = '$tableName'";
					break;
				case 'SQLITE' :
					$sql = 'PRAGMA table_info (' . $tableName . ') ';
					break;
				case 'ORACLE' :
				case 'OCI' :
					$sql = "SELECT a.column_name \"Name\",data_type \"Type\",decode(nullable,'Y',0,1) notnull,data_default \"Default\",decode(a.column_name,b.column_name,1,0) \"pk\" " . "FROM user_tab_columns a,(SELECT column_name FROM user_constraints c,user_cons_columns col " . "WHERE c.constraint_name=col.constraint_name AND c.constraint_type='P' and c.table_name='" . strtoupper ( $tableName ) . "') b where table_name='" . strtoupper ( $tableName ) . "' and a.column_name=b.column_name(+)";
					break;
				case 'PGSQL' :
					$sql = 'select fields_name as "Name",fields_type as "Type",fields_not_null as "Null",fields_key_name as "Key",fields_default as "Default",fields_default as "Extra" from table_msg(' . $tableName . ');';
					break;
				case 'IBASE' :
					break;
				case 'MYSQL' :
				default :
					$sql = 'DESCRIBE ' . $tableName; //备注: 驱动类不只针对mysql，不能加``
			}
		}
		$result = $this->query ( $sql );
		$info = array ();
		if ($result) {
			foreach ( $result as $key => $val ) {
				$val ['Name'] = isset ( $val ['name'] ) ? $val ['name'] : $val ['Name'];
				$val ['Type'] = isset ( $val ['type'] ) ? $val ['type'] : $val ['Type'];
				$name = strtolower ( isset ( $val ['Field'] ) ? $val ['Field'] : $val ['Name'] );
				$info [$name] = array ('name' => $name, 'type' => $val ['Type'], 'notnull' => ( bool ) (((isset ( $val ['Null'] )) && ($val ['Null'] === '')) || ((isset ( $val ['notnull'] )) && ($val ['notnull'] === ''))), // not null is empty, null is yes
'default' => isset ( $val ['Default'] ) ? $val ['Default'] : (isset ( $val ['dflt_value'] ) ? $val ['dflt_value'] : ""), 'primary' => isset ( $val ['Key'] ) ? strtolower ( $val ['Key'] ) == 'pri' : (isset ( $val ['pk'] ) ? $val ['pk'] : false), 'autoinc' => isset ( $val ['Extra'] ) ? strtolower ( $val ['Extra'] ) == 'auto_increment' : (isset ( $val ['Key'] ) ? $val ['Key'] : false) );
			}
		}
		return $info;
	}
	
	/**
     +----------------------------------------------------------
	 * 取得数据库的表信息
     +----------------------------------------------------------
	 * @access public
     +----------------------------------------------------------
	 * @throws ThinkExecption
     +----------------------------------------------------------
	 */
	public function getTables($dbName = '') {
		if (C ( 'DB_FETCH_TABLES_SQL' )) {
			// 定义特殊的表查询SQL
			$sql = str_replace ( '%db%', $dnName, C ( 'DB_FETCH_TABLES_SQL' ) );
		} else {
			switch ($this->dbType) {
				case 'ORACLE' :
				case 'OCI' :
					$sql = 'SELECT table_name FROM user_tables';
					break;
				case 'MSSQL' :
				case 'SQLSRV' :
					$sql = "SELECT TABLE_NAME	FROM INFORMATION_SCHEMA.TABLES WHERE TABLE_TYPE = 'BASE TABLE'";
					break;
				case 'PGSQL' :
					$sql = "select tablename as Tables_in_test from pg_tables where  schemaname ='public'";
					break;
				case 'IBASE' :
					// 暂时不支持
					throw_exception ( L ( '_NOT_SUPPORT_DB_' ) . ':IBASE' );
					break;
				case 'SQLITE' :
					$sql = "SELECT name FROM sqlite_master WHERE type='table' " . "UNION ALL SELECT name FROM sqlite_temp_master " . "WHERE type='table' ORDER BY name";
					break;
				case 'MYSQL' :
				default :
					if (! empty ( $dbName )) {
						$sql = 'SHOW TABLES FROM ' . $dbName;
					} else {
						$sql = 'SHOW TABLES ';
					}
			}
		}
		$result = $this->query ( $sql );
		$info = array ();
		foreach ( $result as $key => $val ) {
			$info [$key] = current ( $val );
		}
		return $info;
	}
	
	/**
     +----------------------------------------------------------
	 * limit分析
     +----------------------------------------------------------
	 * @access protected
     +----------------------------------------------------------
	 * @param mixed $lmit
     +----------------------------------------------------------
	 * @return string
     +----------------------------------------------------------
	 */
	protected function parseLimit($limit) {
		$limitStr = '';
		if (! empty ( $limit )) {
			switch ($this->dbType) {
				case 'PGSQL' :
				case 'SQLITE' :
					$limit = explode ( ',', $limit );
					if (count ( $limit ) > 1) {
						$limitStr .= ' LIMIT ' . $limit [1] . ' OFFSET ' . $limit [0] . ' ';
					} else {
						$limitStr .= ' LIMIT ' . $limit [0] . ' ';
					}
					break;
				case 'MSSQL' :
				case 'SQLSRV' :
					break;
				case 'IBASE' :
					// 暂时不支持
					break;
				case 'ORACLE' :
				case 'OCI' :
					break;
				case 'MYSQL' :
				default :
					$limitStr .= ' LIMIT ' . $limit . ' ';
			}
		}
		return $limitStr;
	}
	
	/**
     +----------------------------------------------------------
	 * 关闭数据库
     +----------------------------------------------------------
	 * @access public
     +----------------------------------------------------------
	 */
	public function close() {
		$this->_linkID = null;
	}
	
	/**
     +----------------------------------------------------------
	 * 数据库错误信息
	 * 并显示当前的SQL语句
     +----------------------------------------------------------
	 * @access public
     +----------------------------------------------------------
	 * @return string
     +----------------------------------------------------------
	 */
	public function error() {
		if ($this->PDOStatement) {
			$error = $this->PDOStatement->errorInfo ();
			$this->error = $error [2];
		} else {
			$this->error = '';
		}
		if ($this->debug && '' != $this->queryStr) {
			$this->error .= "\n [ SQL语句 ] : " . $this->queryStr;
		}
		return $this->error;
	}
	
	/**
     +----------------------------------------------------------
	 * SQL指令安全过滤
     +----------------------------------------------------------
	 * @access public
     +----------------------------------------------------------
	 * @param string $str  SQL指令
     +----------------------------------------------------------
	 * @return string
     +----------------------------------------------------------
	 */
	public function escapeString($str) {
		switch ($this->dbType) {
			case 'PGSQL' :
			case 'MSSQL' :
			case 'SQLSRV' :
			case 'IBASE' :
			case 'MYSQL' :
				return addslashes ( $str );
			case 'SQLITE' :
			case 'ORACLE' :
			case 'OCI' :
				return str_ireplace ( "'", "''", $str );
		}
	}
	
	/**
     +----------------------------------------------------------
	 * 获取最后插入id
     +----------------------------------------------------------
	 * @access public
     +----------------------------------------------------------
	 * @return integer
     +----------------------------------------------------------
	 */
	public function getLastInsertId() {
		switch ($this->dbType) {
			case 'PGSQL' :
			case 'SQLITE' :
			case 'MSSQL' :
			case 'SQLSRV' :
			case 'IBASE' :
			case 'MYSQL' :
				return $this->_linkID->lastInsertId ();
			case 'ORACLE' :
			case 'OCI' :
				$sequenceName = $this->table;
				$vo = $this->query ( "SELECT {$sequenceName}.currval currval FROM dual" );
				return $vo ? $vo [0] ["currval"] : 0;
		}
	}

}